Metrics and Models for Measuring Behavioral Development in Rodents. The proposed research has two basic aims: The first aim is to determine what kinds of behavioral metrics in infant rats are most predictive of adult behaviors. The approach developed here, will have broad application to rodents and should be especially relevant to behavioral phenotyping of rodents during development. The second aim is to develop agent-based models that provide a novel way to analyze behavior in both infant and adult rats, and, which will provide theoretical interpretations that are not possible with traditional statistical techniques. These models will be developed for both infant and adult animals. They will be developed on an open-source platform, which is written in Java and usable on all major operating systems. Users who are not experts in the development of agent- based models will be able to use these models-for appropriate data sets-just as they use popular statistical programs to analyze data. The methodological goals laid out in these aims will be accomplished using vasopressin deficient Brattleboro rats, which are a potentially important model organism for several developmental disorders, including autism spectrum disorders. Since juvenile Brattleboro rats exhibit early locomotor and social differences from wild type rats and adult Brattleboro rats exhibit social and cognitive deficits, this is an ideal model organism to use in developing these methods. It is hypothesized that the measurement and analysis of infant rat locomotion and aggregation will be predictive of adult social and cognitive (e.g., learning and memory) behavior. That is, we will be able to predict from metrics of aggregation and locomotion, differences in performance of wild type and vasopressin deficient rats as adults in several standard behavioral tests of learning, memory, and social behavior. Moreover, the agent-based models developed for this project will greatly enhance traditional statistical analyses, allowing for the novel theoretical interpretation of results. Indeed, it may even be possible one day to test out drugs or other therapeutic treatments on simulated animals before investing the time and resources on actual animal testing. PUBLIC HEALTH RELEVANCE: One aim of the proposed research is to develop metrics of the dynamics of early behavior and connect them to adult behavior in rats and ultimately other rodent animal models. A second aim is to build agent-based models for different behavioral tests, which will help us analyze and explain mechanisms underlying adult behavior, learning, memory and social interactions. Indeed, it may even be possible one day to test out drugs or other therapeutic treatments on simulated animals before investing the time and resources on actual animal testing.